Lock



FIG. 1 is a front perspective view of a lock showing my new design;

FIG. 2 is a top view of the lock of FIG. 1;

FIG. 3 is a front view of the lock of FIG. 1;

FIG. 4 is a rear view of the lock of FIG. 1;

FIG. 5 is a bottom view of the lock of FIG. 1;

FIG. 6 is a right side view of the lock of FIG. 1; and,

FIG. 7 is a left side view of the lock of FIG. 1.

The broken lines shown represent unclaimed subject matter and form no part of the claimed design. 

I claim the ornamental design for a lock, as shown and described. 